Comparison of fatty acids in the brains of wild and reared sea bass Dicentrarchus labrax L. and sea bream Sparus aurata L., and living in the same natural environment

Abstract

This study has assessed the fatty acid contents in the brains of two perciform species, sea bass (Dicentrarchuslabrax) and sea bream (Sparusaurata), and comparisons are made between them in both their natural environment and under conditions of artificial cultivation. The sea bass appears to have a more intensive brain metabolism than sea bream. This is attributed mainly to the respective genetic make-ups rather than to the feed each species may consume. Saturated and mono-unsaturated fatty acids in the brains of wild fish were at higher levels than in the brains of reared fish. The n-3 class were measured at about double the quantities of those found for the n-3 class in the wild fish of both species, but a reverse trend was apparent for the reared fish. The n-3/n-6 ratio from the brains of wild fish was almost double that from the brains in reared fish. The absence of the C20:5n-3 (EPA) from the brains of the wild fish, in both species, as well as from the brains of the reared sea bass probably suggests a high metabolic rate which, in these fishes, is oriented to the production of C22:6n-3 which is needed for the structure and function of cellular membranes in the fast developing brains of younger fish.